During the manufacture of magnetic or optical recording media, such as floppy disks, hard disks, CD ROM disks, magneto-optical disks, and the like, many process steps require that the disk be releasably mounted to a rotatable arbor. Such process steps may include application of surface coatings, as well as cleaning, polishing, burnishing, and testing.
There are known in the prior art various forms of rotating disk chucks for releasably mounting a disk. Data disks must conform to extremely close tolerances for planarity, surface finish, and coating integrity, which requires that the chuck securing a disk during processing must grip the disk with a high degree of concentricity and planarity, and cannot impart any curvature or warping to the disk. Moreover, the chuck must grip the disk only at portions that will not be used for data recording. An improved disk chuck is desired.